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MANUAL OF MODERN VITICULTURE. 



which propagate mildew in summer ; they should, therefore, 

 be used before the disease has made its appearance ; that is to 

 say, towards the 15th of May in the Mediterranean regions.* 

 But, as new leaves develop in course of time, it is necessary, 

 to protect them, to further treat the vines. The second 

 treatment should be made at the beginning of July, and a 

 third towards the 15th of August. It may even be necessary 



Fig. 151. Vermorel's Spray-pump (section). 



to give a fourth treatment after the vintage, so as to enable 

 the wood to ripen normally. However, vine-growers must 

 be guided by the atmospherical conditions being more or less 

 favorable to the development of the disease. 



The liquids should be finely sprayed, as the object is not 

 to accumulate a large quantity of copper on a certain spot, 

 but to spread it everywhere ; that is to say, on every part of 

 the plant where drops of dew may be formed. Spray-pumps 



* Towards the middle of Novembi r in Victoria. 



